With the advance of data communication technologies, mobile phones have evolved to multifunctional portable devices by integrating various functional modules such as camera, music player, and digital broadcast receiver.
As more and more functions are integrated into a mobile phone, the mobile phone has had to deal with and store a large and wide variety of data. For this reason, recent mobile phones are required to secure large storage space. In order to expand the storage capacity of a mobile phone, various external storage devices such as MultiMediaCard (MMC) and universal serial bus (USB) memory. Using such an external storage device, the data stored in the mobile phone can be copied to and even modified in another device (e.g., personal computer).
In a case that the data are stored in the MMC or USB memory, the mobile phone should synchronize metadata of the data between a database and a file system of the mobile phone whenever the MMC or USB memory is attached to and/or detached from the mobile phone.
In order to synchronize the metadata managed in a database, a conventional data synchronization method initializes the database managing the metadata and restructures the database with the metadata (i.e., the file information managed in the file system). However, the conventional data synchronization method has a shortcoming that it takes so long time to synchronize the metadata between the database and the file system of the mobile phone.